This project will 1) evaluate the efficacy of a comprehensive, multi-grade, multi-year program, the Positive Action program (PA) designed to reduce student problem behaviors (including drug use and violence), disciplinary referrals and suspensions, and academic underachievement; 2) evaluate the effects of the program on the presumed/theoretical mediator variables; and 3) assess which of these changes in mediator variables actually mediate the effects of the program on behavior and school performance. The Hawaiian school district has agreed to implement a randomized efficacy trial of the PA program. We will randomly assign schools to PA or control conditions from strata matched on multiple indicators of risk. PA schools will receive the full PA program for four years (the 2001-02 through 2004-05 school years). This includes all materials for all students (at all grades), families, teachers, and principal, plus community kits; all training for teachers and other interested staff, and continuous technical support and monitoring by a PA staff person. Data on behavior and academic achievement will be obtained from school archival records for all students for all years and, where appropriate for several years prior to the study. Students in grades 1 and 3 in the 200 1-02 school year and their parents and teachers will also be followed through the project with surveys every year. The subject population will contain equal portions of males and females, and proportionate numbers of the major ethnic groups on Oahu (Hawaiian or part Hawaiian, white, Asian, Other). Analyses will test for program effects on all hypothesized mediating variables and outcomes, and the hypothesized mediational pathways. We expect to apply for a competitive continuation to continue the study and follow the younger cohort into middle school and the older cohort into high school.